// Copyright (c) 2019 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package index

// Keys returns a slice of the keys in the cache, from oldest to newest. Used for
// testing only.
func (c *postingsListLRU) keys() []PostingsListCacheKey {
	var keys []PostingsListCacheKey
	for _, shard := range c.shards {
		keys = append(keys, shard.keys()...)
	}
	return keys
}

// Keys returns a slice of the keys in the cache, from oldest to newest. Used for
// testing only.
func (c *postingsListLRUShard) keys() []PostingsListCacheKey {
	keys := make([]PostingsListCacheKey, 0, len(c.items))
	for ent := c.evictList.Back(); ent != nil; ent = ent.Prev() {
		entry := ent.Value.(*entry)
		keys = append(keys, entry.key)
	}
	return keys
}
